Automated media storage libraries are known for providing cost effective access to large quantities of stored media. Generally, media storage libraries include a large number of storage slots on which are stored portable data storage media. The typical portable data storage media is a tape cartridge, an optical cartridge, a disk cartridge, electronic storage media, and the like. By “electronic storage media,” Applicant mean a device such as a PROM, EPROM, EEPROM, Flash PROM, compactflash, smartmedia, and the like.
One (or more) accessor(s) typically accesses the data storage media from the storage slots and delivers the accessed media to a data storage device for reading and/or writing data on the accessed media. Suitable electronics operate the accessor(s) and operate the data storage device(s) to provide information to, and/or to receive information from, an attached on-line host computer system.
Prior art apparatus and methods to read information from a magnetic tape information storage medium initially read calibration information from a calibration region on the tape, and identify one or more valid calibration signals. The phase and frequency of the calibration signals are determined only if a sufficient number of valid calibration signals are detected.
Such prior art methods require a lengthy calibration region and a two step process to determine the phase and frequency of the calibration information encoded within the calibration region. What is needed is an apparatus and method to detect a plurality of valid calibration signals while simultaneously determining the phase and frequency of the information encoded in those calibration signals.